Hi all- I have a GSG-5 carbine with a few hundred rounds through it. I've had no problems with it, I'm just quite interested in the PK! It is entirely stock other than a cocking-tube buffer and a black sling from a member here. I also have a replacement front grip for it, which has 3 rails attached. All I am looking for is a GSG-5PK with the threaded barrel. If you have the 1/2x28" threaded adapter as well, I'd be extremely happy!